Abstract
Aeration is a common remediation technique to mitigate greenhouse gas emissions and accelerate waste biodegradation in landfills. However, designing of landfill aeration remains challenging. Enhancing the understanding of concurrent methane (CH4) oxidation and aerobic biodegradation of waste during landfill aeration is crucial. This study combined laboratory experiments with simplified modeling to elucidate these two processes occurring in waste after different biodegradation periods. As biodegradation period of waste increased, the CH4 consumption rates decreased, suggesting a gradual change in microbial community. The oxygen (O2) consumption rates initially increased and then decreased in three reactors with the different concentrations of CH4 at the beginning of the reaction (initial CH4 concentration) of 20 %, 17 %, and 10 %. The peak O2 consumption rates were −0.048, −0.063, and −0.072 mol day−1 kg−1 dry mass, respectively. A simplified model was developed based on the chemical reaction equations, balance equations, and elemental analysis of degradable waste to quantify the molar fractions of O2 consumption attributed to CH4 oxidation and aerobic waste biodegradation. The molar fraction of O2 consumption by CH4 oxidation ranged from 1 % to 88 %. The CH4 removal efficiency ranged from 4 % to 16 %, which was influenced by the competing aerobic waste biodegradation and was lower than values reported in studies using compost materials, such as garden waste or natural soil as substrates. Nevertheless, CH4 oxidation in shallow layers of landfill contributes to overall CH4 oxidation globally. This study provides a valuable dataset and theoretical support for optimizing aeration design and mitigating CH4 emissions from landfills.
Original language | English |
---|---|
Article number | 125282 |
Journal | Journal of Environmental Management |
Volume | 381 |
DOIs | |
Publication status | Published - May 2025 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2025
ASJC Scopus Subject Areas
- Environmental Engineering
- Waste Management and Disposal
- Management, Monitoring, Policy and Law
Keywords
- Aeration
- Aerobic biodegradation
- Methane oxidation
- Municipal solid waste
- Simplified model